ClickHouse/contrib/libzlib-ng/arch/x86/x86.c

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/*
* x86 feature check
*
* Copyright (C) 2013 Intel Corporation. All rights reserved.
* Author:
* Jim Kukunas
*
* For conditions of distribution and use, see copyright notice in zlib.h
*/
#include "x86.h"
ZLIB_INTERNAL int x86_cpu_has_sse2;
ZLIB_INTERNAL int x86_cpu_has_sse42;
ZLIB_INTERNAL int x86_cpu_has_pclmulqdq;
#ifdef _MSC_VER
#include <intrin.h>
#else
// Newer versions of GCC and clang come with cpuid.h
#include <cpuid.h>
#endif
static void cpuid(int info, unsigned* eax, unsigned* ebx, unsigned* ecx, unsigned* edx) {
#ifdef _MSC_VER
unsigned int registers[4];
__cpuid(registers, info);
*eax = registers[0];
*ebx = registers[1];
*ecx = registers[2];
*edx = registers[3];
#else
unsigned int _eax;
unsigned int _ebx;
unsigned int _ecx;
unsigned int _edx;
__cpuid(info, _eax, _ebx, _ecx, _edx);
*eax = _eax;
*ebx = _ebx;
*ecx = _ecx;
*edx = _edx;
#endif
}
void ZLIB_INTERNAL x86_check_features(void) {
unsigned eax, ebx, ecx, edx;
cpuid(1 /*CPU_PROCINFO_AND_FEATUREBITS*/, &eax, &ebx, &ecx, &edx);
x86_cpu_has_sse2 = edx & 0x4000000;
x86_cpu_has_sse42 = ecx & 0x100000;
x86_cpu_has_pclmulqdq = ecx & 0x2;
}